It is very common nowadays for any web browser such as Mozilla Firefox, Internet Explorer 7, Maxthon, Opera and etc to have tabs. Tabbed browsing in web browser lets you load Web pages in separate tabs of a single browser window, so you can jump between them quickly and easily. Perhaps you’re reading a news story and want to follow an interesting link without losing your place in the original story. With tabbed browsing, you can do this without filling your desktop with new, unorganized browser windows.
Not only that, compare running 7 Internet Explorer browser with 1 Internet Explorer with 7 tabs. You’ll notice that your computer will start to crawl slowly on the computer that’s running 7 IE browser.
Now, you can also have tabs in your Windows Explorer! Microsoft should have implemented this feature in Windows Vista!

Quizo, a japanese has created QT TabBar that will add-on tab function to your explorer. It’s not a third party program that replaces your explorer… Installation is very easy. Just download the zip archive, extract to a new folder and run RegisterQTTabBar.exe.

Make sure that the Install button is selected and click on the next button. A few seconds later, you’ll get a message saying “Types registered successfully“. You have to restart or logoff and relogin to start having Tabs in your Explorer.
After relogon, you need to open explorer, and right click on toolbar. Check “QT TabBar“. First time you’ll see an empty tab. Close explorer window, and from next time QT TabBar will work properly.

The default shortcut key to go around the tabs in explorer is similar to Firefox browser. You can however edit the default shortcut keys with QTShortcutKeyEditor.exe
Ctrl + Shift + Tab: select previous tab
Ctrl + Num0 – Num9: select a tab directly
Ctrl + W: close current tab
Ctrl + Shift + W: close all but current and locked
Ctrl + Shift + Z: restore a tab
Ctrl + O: open dialog for folder
Ctrl + L: lock/unlock current tab
Ctrl + Shift + L: lock/unlock all tabs
Ctrl + N: clone current tab
Alt + Left/Right: go back/forward
Alt + Ctrl + Left/Right: go back to the start/forward to the end
Alt + F4: close window
Alt + ,: show applicaton menu
Alt + .: show current tab menu
Alt + M: show/hide menu bar (Vista)
You can even set password to any folders. It’s an extra added feature for QT TabBar. Simply right click on the tab and select “Set Password…“. After you’ve set a password to a folder, when you try to access the folder, you’ll be prompted to enter the correct password.

Important Notes: If you’re using Windows XP, make sure Microsoft .NET framework 2.0 or 3.0 is installed on your computer. You can get Microsoft .NET framework 3.0 from Windows Update or download from here.
Very useful and it’s FREE. Highly recommended for power users!
[ Download QT TabBar | Website ]